The present invention relates generally to an automatic adjustment method of the main shaft dynamic balance, and more particularly to an automatic adjustment method of the concealed main shaft dynamic balance.
The dynamic balance precision of the main shaft is crucial to the precision with which a workpiece is processed by a tool or grinding wheel at a high speed ranging between 20000 rpm and 250000 rpm.
As shown in FIG. 1, a prior art method for adjusting the main shaft dynamic balance involves the use of a dynamic balance instrument 10 which is mounted at the external portion of the main shaft of a processing machine, a dynamic balance instrument controller 11 and two dynamic balance rings 12 mounted respectively at two ends of the main shaft. The calibration of the dynamic balance is attained by the two dynamic balance rings 12 in conjunction with the dynamic balance instrument 10 by means of which the dynamic imbalance is measured. On the basis of the dynamic imbalance, the required weight is calculated. The adjustment of the dynamic balance of the main shaft is done manually. This manual adjustment method is generally used before a processing machine is shipped out of the premises of a maker of the processing machine. In other words, such a prior art method as described above can not be employed to adjust the dynamic balance of the main shaft of a processing machine in operation.
As shown in FIG. 2, another prior art method for adjusting the dynamic balance of the main shaft involves the use of an automatic adjustment mechanism 13 which is mounted on one end of the main shaft and is formed of two rotary rings 14. The rotary rings 14 are provided with particles (not shown in the drawing). The processing machine is externally provided with a dynamic balance external controller 15 which is connected with the automatic adjustment mechanism 13 for measuring the phase difference of the particles of the two rotary rings 14. The two rotary rings 14 are adjusted by means of the automatic adjustment mechanism 13, thereby resulting in the correction of the phase difference. This prior art method is complicated in design and is therefore not cost-effective. For example, it uses the complicated and costly circuit. In addition, the automatic adjustment mechanism 13 and the rotary rings 14 take up too much of the available space.
The primary objective of the present invention is to provide an automatic adjustment method of the concealed main shaft dynamic balance, which involves the application of a micro-electromechanical technique to the deposition of a frequency spectrum analyzer in the interior of a main shaft for analyzing the dynamic imbalance of the main shaft with precision. The analysis data are transmitted by radio.
It is another objective of the present invention to provide an automatic adjustment method of the concealed main shaft dynamic balance. The method is precise in view of the basis of the phase difference of the rotary rings in conjunction with the error of the step-by-step motor automatic adjustment main shaft dynamic balance. A permanent magnet and a coil are directly disposed on a spindle by means of which the power is provided internally.
The method of the present invention comprises a first step in which the main shaft is provided with two rotary rings. The rotary rings are provided with a particle and an electromagnetic structure. The main shaft is internally provided with an automatic adjustment mechanism of dynamic balance, a step-by-step motor for actuating the rotary rings, and a dynamic balance analyzer. The interior of the main shaft is provided with a frequency spectrum analyzer made by a micro-electromechanical technique. The spindle of the main shaft is radially provided with at least one permanent magnet which is circumvented by a coil.